powerpc: Merge 32 and 64-bit dma code
We essentially adopt the 64-bit dma code, with some changes to support
32-bit systems, including HIGHMEM. dma functions on 32-bit are now
invoked via accessor functions which call the correct op for a device based
on archdata dma_ops. If there is no archdata dma_ops, this defaults
to dma_direct_ops.
In addition, the dma_map/unmap_page functions are added to dma_ops
because we can't just fall back on map/unmap_single when HIGHMEM is
enabled. In the case of dma_direct_*, we stop using map/unmap_single
and just use the page version - this saves a lot of ugly
ifdeffing. We leave map/unmap_single in the dma_ops definition,
though, because they are needed by the iommu code, which does not
implement map/unmap_page. Ideally, going forward, we will completely
eliminate map/unmap_single and just have map/unmap_page, if it's
workable for 64-bit.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c
index 124f867..41fdd48 100644
--- a/arch/powerpc/kernel/dma.c
+++ b/arch/powerpc/kernel/dma.c
@@ -16,21 +16,30 @@
* This implementation supports a per-device offset that can be applied if
* the address at which memory is visible to devices is not 0. Platform code
* can set archdata.dma_data to an unsigned long holding the offset. By
- * default the offset is zero.
+ * default the offset is PCI_DRAM_OFFSET.
*/
static unsigned long get_dma_direct_offset(struct device *dev)
{
- return (unsigned long)dev->archdata.dma_data;
+ if (dev)
+ return (unsigned long)dev->archdata.dma_data;
+
+ return PCI_DRAM_OFFSET;
}
-static void *dma_direct_alloc_coherent(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t flag)
+void *dma_direct_alloc_coherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flag)
{
+#ifdef CONFIG_NOT_COHERENT_CACHE
+ return __dma_alloc_coherent(size, dma_handle, flag);
+#else
struct page *page;
void *ret;
int node = dev_to_node(dev);
+ /* ignore region specifiers */
+ flag &= ~(__GFP_HIGHMEM);
+
page = alloc_pages_node(node, flag, get_order(size));
if (page == NULL)
return NULL;
@@ -39,27 +48,17 @@
*dma_handle = virt_to_abs(ret) + get_dma_direct_offset(dev);
return ret;
+#endif
}
-static void dma_direct_free_coherent(struct device *dev, size_t size,
- void *vaddr, dma_addr_t dma_handle)
+void dma_direct_free_coherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_handle)
{
+#ifdef CONFIG_NOT_COHERENT_CACHE
+ __dma_free_coherent(size, vaddr);
+#else
free_pages((unsigned long)vaddr, get_order(size));
-}
-
-static dma_addr_t dma_direct_map_single(struct device *dev, void *ptr,
- size_t size,
- enum dma_data_direction direction,
- struct dma_attrs *attrs)
-{
- return virt_to_abs(ptr) + get_dma_direct_offset(dev);
-}
-
-static void dma_direct_unmap_single(struct device *dev, dma_addr_t dma_addr,
- size_t size,
- enum dma_data_direction direction,
- struct dma_attrs *attrs)
-{
+#endif
}
static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
@@ -85,20 +84,44 @@
static int dma_direct_dma_supported(struct device *dev, u64 mask)
{
+#ifdef CONFIG_PPC64
/* Could be improved to check for memory though it better be
* done via some global so platforms can set the limit in case
* they have limited DMA windows
*/
return mask >= DMA_32BIT_MASK;
+#else
+ return 1;
+#endif
+}
+
+static inline dma_addr_t dma_direct_map_page(struct device *dev,
+ struct page *page,
+ unsigned long offset,
+ size_t size,
+ enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ BUG_ON(dir == DMA_NONE);
+ __dma_sync_page(page, offset, size, dir);
+ return page_to_phys(page) + offset + get_dma_direct_offset(dev);
+}
+
+static inline void dma_direct_unmap_page(struct device *dev,
+ dma_addr_t dma_address,
+ size_t size,
+ enum dma_data_direction direction,
+ struct dma_attrs *attrs)
+{
}
struct dma_mapping_ops dma_direct_ops = {
.alloc_coherent = dma_direct_alloc_coherent,
.free_coherent = dma_direct_free_coherent,
- .map_single = dma_direct_map_single,
- .unmap_single = dma_direct_unmap_single,
.map_sg = dma_direct_map_sg,
.unmap_sg = dma_direct_unmap_sg,
.dma_supported = dma_direct_dma_supported,
+ .map_page = dma_direct_map_page,
+ .unmap_page = dma_direct_unmap_page,
};
EXPORT_SYMBOL(dma_direct_ops);